# 条件判断
def usernameStr(username1,username2):
    if username1.startswith('p') and username2.startswith('p'):
        print('username startwith p')
    elif username1.startswith('P') and username2.startswith('P'):
        print('username startwith P')
    elif username1.lower() == username2.upper():
        print('lower==upper')
    elif not username1==username2:
        print("username1 not equals username2")
    else:
        print('else')

if __name__ == '__main__':
    usernameStr('Python', 'python')